2021 Engine thread

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
wuzak
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Re: 2021 Engine thread

Post by wuzak » Thu May 30, 2019 4:18 am

Tommy Cookers wrote:
Wed May 29, 2019 9:06 am
isn't exhaust turbine-recoverable power ('blowdown power') available without back pressure ?
It is, or at least minimal back pressure increase. It won't provide the recovered power he is dreaming of.

Tommy Cookers wrote:
Wed May 29, 2019 9:06 am
isn't electric motoring not much used at low speeds as the car is then traction-limited even on ICE power alone ?
In the current cars yes, because they have shed loads of low down power.

The N/A V8s, however, do not have nearly the same amount.

wuzak
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Re: 2021 Engine thread

Post by wuzak » Thu May 30, 2019 4:29 am

Zynerji wrote:
Wed May 29, 2019 2:31 pm
Just the heads, probably a derivative of the current v6 tech. They have already proven bulletproof reliability of their V8 short blocks. By updating the short block with the current V6 head technology, I believe they can get 20000 RPM pretty reasonably at a good fuel consumption. The real question is, does TJI have any benefit in a non boosted engine, and does the VLIM supercharge enough to offset this restriction.
The fuel consumption of the V8s was at least 50% greater than the current engines.

Zynerji wrote:
Wed May 29, 2019 2:31 pm
Hardly. Please provide math/proof since you are stating this as a fact. And these are GU, not MGU. We currently have 6 into 1, where my idea would have 4 into 1, but half the size. And 20000 RPM instead of 12000 should overcome this concern. Even running twin, current sized units at 1.2L each, instead of 1.6L would probably work as you are deleting the work done by the compressor.
The exhaust has to transfer some of its energy to the turbine in order to generate power in the GU-H (what is the difference between an MGU and a GU?). That will reduce the volume of the exhaust.

The pitch of the engine will change by a small amount (4 x 20,000 = 80,000 vs 6 x 12,000 = 72,000), but how much the turbine in the exhaust dulls the sound I do not know.

Zynerji wrote:
Wed May 29, 2019 2:31 pm
2.4l v8 was about 875hp, 225ft-lb @ 18000rpm. Adding another 200-300hp through the GU-H -> MU-K would increase low end torque, and high rpm power. Battery loss saves huge amounts of weight. Front Hub motors will add about 7kg to each wheel. I think my suggestion would still come at a net lowering of weight, and a net increase of tractive power from AWD.
The V8s never made that much power. even with 80hp from KERS.

The V8s were in the region of 750hp to 800hp, most likely at the lower end of that scale when the rpm limit was set to 18,000rpm.

Losing the battery saves ~30kg. How much does your capacitor weigh?

Zynerji wrote:
Wed May 29, 2019 7:35 pm
I wouldn't be against a 2.4Lv6-NA-DI-TJI-VVT with the twin GU-H, integrated 300kW MU-K and 18000+RPM with 120kW hub motors in the front wheels. A 1200eHP-AWD formula?? Yes, please!!

The real question then becomes about how far you could push the GU-H/MU-K if the design specialized in ONLY recovery/deployment instead of the hybrid MGU tech. I may be open to ammending my "dream" idea to include MGU-K front hub motors if we can get a counter-rotating twin MLC flywheel in the nose for recovery/storage/stabilization... [-o<
It would make sense that if you have motors in the front wheels that you also use them as generators, since most braking effort is in the front wheels (about 60/40 with the current weight distribution?).

7kg is significant additional weight in the hubs. Better to have a chassis mounted MGU with driveshafts.

A flywheel would be OK so long as it has better energy density than a battery. If the battery weighs less than the flywheel for the same storage then it would be the better option.

In either case, it would be better suited in the current location instead of out on the nose.

wuzak
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Re: 2021 Engine thread

Post by wuzak » Thu May 30, 2019 4:37 am

saviour stivala wrote:
Wed May 29, 2019 4:28 pm
Comes 2021 and you lot will find that a lot of time and space had been wasted on this here subject wish list because the present engines/power units used will be exactly the same. So it’s best to change the subject to at minimum 2025.
This was pretty much decided last year. Only a few details are to be sorted out (fuel flow rate, rpm, MGUK power/operation).

roon
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Re: 2021 Engine thread

Post by roon » Thu May 30, 2019 5:20 am

wuzak wrote:
Thu May 30, 2019 4:29 am
...but how much the turbine in the exhaust dulls the sound I do not know.
I believe the turbines currently in use at 100k RPM and maybe 12 blades will produce sound at the upper threshold of human hearing--something like 20k Hz. A larger, slower turbine would be more audible to perhaps better accentuate the exhaust pulse sound.

wuzak wrote:
Thu May 30, 2019 4:29 am
...most braking effort is in the front wheels (about 60/40 with the current weight distribution?).
I don't know but weight distribution and little weight transfer available to the F1 chassis suggests more kinetic energy is available to the rear axle. In practice braking feel or stability may prevent a brake balance that is equal to weight distribution. Is that the case? That said, the rear brake discs and calipers look as big as the front, and of course the rear tires are larger. Aero CoP will also determine the balance used--I'm not sure how far off that is from the center of mass in a current F1 rig.

wuzak
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Re: 2021 Engine thread

Post by wuzak » Thu May 30, 2019 5:43 am

roon wrote:
Thu May 30, 2019 5:20 am
wuzak wrote:
Thu May 30, 2019 4:29 am
...most braking effort is in the front wheels (about 60/40 with the current weight distribution?).
I don't know but weight distribution and little weight transfer available to the F1 chassis suggests more kinetic energy is available to the rear axle. In practice braking feel or stability may prevent a brake balance that is equal to weight distribution. Is that the case? That said, the rear brake discs and calipers look as big as the front, and of course the rear tires are larger. Aero CoP will also determine the balance used--I'm not sure how far off that is from the center of mass in a current F1 rig.
The discs are size limited due to the wheel rim diameter.

The front brakes have 6 piston calipers, while the rears have 4 piston calipers, possibly due to braking assistance by the MGUK.

More than 50% of the braking effort is going through the front wheels. Drivers actually adjust the bias from corner to corner. From what I recall seeing, the number is usually between 55% and 60%.

henry
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Re: 2021 Engine thread

Post by henry » Thu May 30, 2019 7:22 am

wuzak wrote:
Thu May 30, 2019 5:43 am

More than 50% of the braking effort is going through the front wheels. Drivers actually adjust the bias from corner to corner. From what I recall seeing, the number is usually between 55% and 60%.
The bias is in the range you quote. This is for the beginning of the stop. As the speed drops the bias reduces. Hence the need to adjust corner by corner, as well as the lesser effect of road incline. The principle cause of this variability is aero downforce.

The regulations allow the brake by wire system to change the bias during the stop. The driver also has control over this with a brake migration setting.

Currently from around 100kph down rear braking is exclusively MGU-K.
Fortune favours the prepared; she has no favourites and takes no sides.
Truth is confirmed by inspection and delay; falsehood by haste and uncertainty : Tacitus

Tommy Cookers
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Re: 2021 Engine thread

Post by Tommy Cookers » Thu May 30, 2019 7:46 am

henry wrote:
Thu May 30, 2019 7:22 am
Currently from around 100kph down rear braking is exclusively MGU-K.
I think ....

'below 100 kph' rear braking (accelerator-off anyway) is exclusively friction
in some part because there's little benefit and some difficulties electrically
and the cutoff point is maybe 130 kph not 100 kph

bbw changing brake bias within the corner - wouldn't this be an impermissible driver aid ?
the present system has no complex division of friction brake pressure
within a braking episode it varies (cuts) only the rear brake friction pressure
simpler and safer


front hub MGs - these would readily become a driver aid
a single front MG acting via a differential wouldn't (so readily)

henry
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Location: England

Re: 2021 Engine thread

Post by henry » Thu May 30, 2019 8:38 am

Tommy Cookers wrote:
Thu May 30, 2019 7:46 am
henry wrote:
Thu May 30, 2019 7:22 am
Currently from around 100kph down rear braking is exclusively MGU-K.
I think ....

'below 100 kph' rear braking (accelerator-off anyway) is exclusively friction
in some part because there's little benefit and some difficulties electrically
and the cutoff point is maybe 130 kph not 100 kph

bbw changing brake bias within the corner - wouldn't this be an impermissible driver aid ?
the present system has no complex division of friction brake pressure
within a braking episode it varies (cuts) only the rear brake friction pressure
simpler and safer


front hub MGs - these would readily become a driver aid
a single front MG acting via a differential wouldn't (so readily)
Had a quick re-read of the regs. I think the requirement that the driver pressure should substitute for the bbw pressure in the event of an absence of bbw pressure would support your statements on safety and perhaps on friction only a low speeds. I’m not convinced though. I’ve seen examples of a Honda and a Ferrari motoring at the very end of stops. I’ve put this down to driving the MGU-K but other explanations are possible.

I have definitely heard discussions between drivers and engineers about brake migration settings. I might be wrong it what their function is. As for driver aid, it might fall into the class of features that allow a driver to shift up entering Barcelona turn 9 flat out at 260kph, or lifting and coasting on the beep.

The lower speed for MGU-K depends on a range of assumptions on tyre mu, aero downforce, CoG height, wheelbase, transmission loss, engine braking etc. 130kph is not unreasonable.

I raised the speed point because big front MGUs might well have quite high speed thresholds at their max power.
Fortune favours the prepared; she has no favourites and takes no sides.
Truth is confirmed by inspection and delay; falsehood by haste and uncertainty : Tacitus

Zynerji
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Joined: Wed Jan 27, 2016 3:14 pm

Re: 2021 Engine thread

Post by Zynerji » Thu May 30, 2019 11:49 pm

Tommy Cookers wrote:
Thu May 30, 2019 7:46 am
henry wrote:
Thu May 30, 2019 7:22 am
Currently from around 100kph down rear braking is exclusively MGU-K.
I think ....

'below 100 kph' rear braking (accelerator-off anyway) is exclusively friction
in some part because there's little benefit and some difficulties electrically
and the cutoff point is maybe 130 kph not 100 kph

bbw changing brake bias within the corner - wouldn't this be an impermissible driver aid ?
the present system has no complex division of friction brake pressure
within a braking episode it varies (cuts) only the rear brake friction pressure
simpler and safer


front hub MGs - these would readily become a driver aid
a single front MG acting via a differential wouldn't (so readily
)
I had thought about this as well, but I don't think it really matters anymore, and having half shaft to the front only makes the aerodynamics even worse.

gruntguru
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Re: 2021 Engine thread

Post by gruntguru » Fri May 31, 2019 5:37 am

Dr. Acula wrote:
Wed May 29, 2019 12:50 pm
In my opinion they can use as much electric power as they want at any time as long as it doesn't violate some specific rules, which means they can potentially use the full power of the MGU-K out of a slow corner and scale back the poweroutput of the ICE accordingly which will be the most efficient way to drive.
In terms of lap time it doesn't matter where the power comes from at traction-limited speeds.

In terms of fuel efficiency it is better to run the ICE at higher loads. Part throttle efficiency would be significantly lower than at full load. Cylinder skipping helps but it is still better to use MGUK energy in the following order of priority:

1. After the traction limited zone at the beginning of the longest straights.

2. Ditto for shorter straights although the returns are diminishing - it will often be better to spend more time powering the MGUK on the longest straight.

3. Obviously both of the above are trumped if there is an opportunity to overtake or a need to defend.
je suis charlie

Tommy Cookers
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Re: 2021 Engine thread

Post by Tommy Cookers » Fri May 31, 2019 9:54 am

gruntguru wrote:
Fri May 31, 2019 5:37 am
... In terms of fuel efficiency it is better to run the ICE at higher loads....
this implies choosing a high gear and low revs

though eg
at 11550 rpm 120 kW will come or go via 100 Nm of MGU-K torque - (and X Amperes of current at Y Volts)
at 5775 rpm 120 kW will come or go via 200 Nm (the cap) K torque - (and 2X Amperes current at Y/2 Volts)
the electrical people won't support the 2X Amperes - it's inefficient
that's why during braking there's intense downshifting to keep revs high and current low

so there's some incompatibility between ICE and K when they're acting together
otherwise the K would become 'bigger' relative to the ICE as rpm reduced

ACRO
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Re: 2021 Engine thread

Post by ACRO » Fri May 31, 2019 10:16 am

wuzak wrote:
Wed May 08, 2019 4:07 am

The 2021 power units will be, largely, as now.

Single turbo with MGUH and MGUK.
in this case the sound will not change much or sound speakers will be introduced .

AMG.Tzan
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Re: 2021 Engine thread

Post by AMG.Tzan » Fri May 31, 2019 10:34 am

ACRO wrote:
Fri May 31, 2019 10:16 am
wuzak wrote:
Wed May 08, 2019 4:07 am

The 2021 power units will be, largely, as now.

Single turbo with MGUH and MGUK.
in this case the sound will not change much or sound speakers will be introduced .
So they won't even increase the power a bit as they first said?? To comfortably go over 1000bhp! IIRC Racecar Engineering in the 2021 rule changes article said that the MGU-K will get a 30kW increase...!

roon
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Re: 2021 Engine thread

Post by roon » Fri May 31, 2019 8:46 pm

https://www.motorsport.com/f1/news/pors ... 1/4414564/

They had a TT V6 in the works for potential use in racing and in a supercar, but VW-Audi pulled out of WEC and F1 stuck with the MGUH.

Who/what benefits from MGUH development? Six+ years on and no road use yet, but F1 keeps it in the mix because of road relevancy or something about efficiency as marketing tactic. How about leave automakers and lawmakers to making their fleets efficient. That's fine. But why does F1 need to pretend to be a part of that?

F1 have proven that they can make a thermally efficient power unit, but this answers a question the auto industry seems to not have been asking. They're more concerned with fuel efficiency, part throttle optimization, and shutting off the ICE as often as possible.

The use cases are so different, road and track.

ENGINE TUNER
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Re: 2021 Engine thread

Post by ENGINE TUNER » Fri May 31, 2019 9:03 pm

roon wrote:
Fri May 31, 2019 8:46 pm
https://www.motorsport.com/f1/news/pors ... 1/4414564/

They had a TT V6 in the works for potential use in racing and in a supercar, but VW-Audi pulled out of WEC and F1 stuck with the MGUH.

Who/what benefits from MGUH development? Six+ years on and no road use yet, but F1 keeps it in the mix because of road relevancy or something about efficiency as marketing tactic. How about leave automakers and lawmakers to making their fleets efficient. That's fine. But why does F1 need to pretend to be a part of that?

F1 have proven that they can make a thermally efficient power unit, but this answers a question the auto industry seems to not have been asking. They're more concerned with fuel efficiency, part throttle optimization, and shutting off the ICE as often as possible.

The use cases are so different, road and track.
F1 only stuck with the mguh because Porsche refused to commit, everyone, including Merc and Ferrari had already publicly agreed to delete the mguh.

The mguh(in one form or another ) is being put to road application by several different manufacturers, including Nissan/Renault and Merc.